This forum is disabled, please visit https://forum.opencv.org
 | 1 | initial version |
The extrinsic matrix is rotation-translation of the camera around scene or scene around camera therefore is normal to get different extrinsic matrix from different scene of same camera.
The intrinsic matrix describes the camera itself and is supposed to be scene independent (but affected by the Reprojection error)
Finally the calibration based on "random pattern" has more features of "chessboard" calibration but is a bit less accurate due to the feature detector/descriptor/extractor like AKAZE or (non-free)SIFT/SURF vs subpixel in the chessboard based algo.
Check the related paper for details:
B. Li, L. Heng, K. Kevin and M. Pollefeys, "A Multiple-Camera System Calibration Toolbox Using A Feature Descriptor-Based Calibration Pattern", in IROS 2013.
At the end, always remember that the contrib modules quite often do not have stable API, and they are not well-tested
